In a survey of 900 adults with ADHD, 75% had tried cannabis and 41% used in the past month. Daily users had higher rates of cannabis use disorder, anxiety, depression, and PTSD compared to non-daily users, and reported that cannabis worsened inattention symptoms.
Adults with ADHD who use or consider using cannabis, and clinicians managing ADHD.
75% of adults with ADHD have tried cannabis; daily users had 62% rates of cannabis use disorder
What the researchers found
Cannabis use was highly prevalent: 75% ever used, 41% past-30-day use. Daily users vs non-daily users showed: higher cannabis use disorder (62% vs 38%), more anxiety (70% vs 48%), more depression (55% vs 41%), more PTSD (30% vs 14%), and reported cannabis worsened inattention. Stimulant misuse rates were comparable. Users reported mixed effects on anxiety: 156 noted improvement while 34 reported worsening.
Why it matters
ADHD is among the most common reasons people self-medicate with cannabis, yet evidence for its effectiveness is lacking. This large survey reveals that while many adults with ADHD perceive benefits, daily cannabis use is associated with significantly worse psychiatric profiles and worsened core ADHD symptoms.
The numbers in context
900 adults with ADHD. 75% ever used cannabis, 41% past-30-day use. Daily users: 62% met criteria for cannabis use disorder (vs 38% non-daily), 70% anxiety (vs 48%), 55% depression (vs 41%), 30% PTSD (vs 14%). Daily users more likely to report cannabis worsened inattention (OR 0.59) and impulsivity (OR 1.69).
How the study worked
Anonymous online survey emailed to 9,274 adults with documented ADHD diagnoses (ICD-10 codes confirmed by self-report). 900 completed the 46-item survey covering demographics, medical history, stimulant use, cannabis use, and impacts on ADHD symptoms. Three groups compared: no recent use (n=458), non-daily use (n=256), daily use (n=112).
What this study cannot tell us
Cross-sectional survey cannot determine causation: people with worse ADHD and more comorbidities may be more likely to use cannabis daily. Self-selected sample with low response rate. Cannabis use disorder was assessed by questionnaire, not clinical interview. Stimulant medication effects were not controlled for.
How to read the evidence
Large survey of clinically diagnosed ADHD patients with validated measures, but cross-sectional and self-selected sample.
When this study was published
Published in 2026, using April-July 2023 survey data.
The bigger picture
The mixed self-reported effects on anxiety (improvement for some, worsening for others) mirror findings in the general population and highlight why individual responses to cannabis are so variable. The association between daily cannabis use and worsened inattention is particularly relevant since inattention is the core functional impairment of ADHD.
Questions still open
- Does cannabis worsen ADHD symptoms directly, or do people with worse symptoms turn to cannabis? Would specific cannabinoid ratios (e.g., high CBD) show different effects on ADHD? How should clinicians address the high prevalence of cannabis use in their ADHD patients?
Common questions
Does cannabis help ADHD?
How common is cannabis use disorder among ADHD adults who use daily?
Read the original research
Cannabis Use in a Community-Based Sample of Adults Diagnosed With ADHD: Prevalence, Impact on Symptoms, and Stimulant Side Effects.
Journal of attention disorders, 30(3), 407-422
Citation
Ryan, Jennie E; Herens, Allison; Fruchtman, Mitchell; Veliz, Philip; Kelly, Erin L; Worster, Brooke. (2026). Cannabis Use in a Community-Based Sample of Adults Diagnosed With ADHD: Prevalence, Impact on Symptoms, and Stimulant Side Effects.. Journal of attention disorders, 30(3), 407-422. https://doi.org/10.1177/10870547251364575
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